The embodiments described herein relate generally to optical imaging and, more particularly, to diffuse optical imaging (DOI) using either traditional near infrared spectroscopy (NIRS) systems or more advanced diffuse optical tomography (DOT) systems.
Optical neuroimaging has never lacked clinical potential, due to its ability to longitudinally and non-invasively monitor brain function. However, progress towards the bedside practice of methods to map brain function, such as functional near infrared spectroscopy (fNIRS), has been hindered by conceptual and technical limitations. One obstacle is that task-based neuroimaging, which is standard in cognitive neuroscience research, is generally ill-suited to clinical populations since they may be unable to perform any task. Recently in functional magnetic resonance imaging (fMRI), it was discovered that even during the absence of overt tasks, fluctuations in brain activity are correlated across functionally-related cortical regions. Thus, the spatial and temporal evaluation of spontaneous neuronal activity has allowed mapping of these resting-state networks (RSNs). Translating these advances to optical techniques would enable new clinical and developmental studies. Yet, mapping spontaneous activity with fNIRS measurements presents significant challenges due to the obscuring influences of superficial signals, systemic physiology, and auto-regulation.
Accordingly, it is desirable to provide a method for using optical imaging to image functional connectivity patterns in the human brain.